Update Ingress API to use NetworkingV1 package & Fix the backend column in kubernetes_ingress table. Fixes #91

[bigdatasourav]

Example query results

Results

> select
  name,
  namespace,
  ingress_class_name as class,
  age(current_timestamp, creation_timestamp)
from
  kubernetes_ingress
order by
  namespace,
  name;
+-----------------+-----------+---------------+----------+
| name            | namespace | class         | age      |
+-----------------+-----------+---------------+----------+
| minimal-ingress | default   | nginx-example | 00:23:30 |
+-----------------+-----------+---------------+----------+
> select
  name,
  namespace,
  jsonb_pretty(rules) as rules
from
  kubernetes_ingress;
+-----------------+-----------+----------------------------------------------+
| name            | namespace | rules                                        |
+-----------------+-----------+----------------------------------------------+
| minimal-ingress | default   | [                                            |
|                 |           |     {                                        |
|                 |           |         "http": {                            |
|                 |           |             "paths": [                       |
|                 |           |                 {                            |
|                 |           |                     "path": "/testpath",     |
|                 |           |                     "backend": {             |
|                 |           |                         "service": {         |
|                 |           |                             "name": "test",  |
|                 |           |                             "port": {        |
|                 |           |                                 "number": 80 |
|                 |           |                             }                |
|                 |           |                         }                    |
|                 |           |                     },                       |
|                 |           |                     "pathType": "Prefix"     |
|                 |           |                 }                            |
|                 |           |             ]                                |
|                 |           |         }                                    |
|                 |           |     }                                        |
|                 |           | ]                                            |
+-----------------+-----------+----------------------------------------------+